Mining machine



Nov. 23, 1943. R K. JEFFREY ET AL 7 2,334,771

MINING MKCHINE Filed March 18, 1939 8 Sheets-Sfiet l Z'Snventors: ROBERT KJEFFREY AND STERLING C. Moom,

Nov. 23, 1943'.

R. K. JEFFREY ET AL MINING MACHINE Filed March 18, 1939 8 Sheets-Sheet 2 3nventons:

ROBERT LEJEFFREY A STERLING C. MOON,

BY 77], M,

(lttomeg.

Npv. 23, 1943. R. K. JEFF REY- ETAL 2,334,771

MINING MACHINE Filed March 18, 1939 8 Sheets-Sheet 3 3nventors ROBE RT K. JEFF REY Gflorneg- STERLIHG C. MOON, B W. WIW

al i m. W

Nov. 23, 1943. R. K. JEFFREY ETAL MINING MACHINE Filed March 18,

1939 8 Sheets-Sheet 4 3nnentors: Roagg' l lgJEFFRex STERLING C MooN,

BY H

(Ittomeg R. K. JEFFREY ET AL Nov. 23, 1943. I

MINING MACHINE 8 Sheets-Sheet 5 Filed March 18, 1959 :Y .x. 5 i .r R o o F M w o K 5 V T W N R R 5 m 0 Mi u N. n o rllll IIL F mm T v S NX MR Nov. 23', 1943.

R.'K. JEFFREY ET AL MINING MACHINE a Sheets-Sheet 6 Filed March 18, 1939 [NVEN ToRs I ROBERT K. JEFFREY AND STERLING C. Moo N,

Nov. 23, 1943. R, K. JEFFREY ET AL 2,334,771

MINING MACHINE,

Filed March 18, 1939 8 Sheets-Sheet 8 233 EILmIB /Nl/ENTORS. ROBERINDK.JEFFREY STERLING C. MooN,

BYGZWI ATT'Y raisniedme2a1943 UNITED STATES earsh t; i

Rebel- 2K1 Je fireyand Sterling CLMoon; Columbus, Ohio, assignors to" 'IheJefiEreyManufac- 'turing Companma corporation of Ohio I H m siiqnreeithlfi 193.9, t aws 1 ulc ims. (01.252528;

I This invention relates to a miningmachine and tem for a miningmachine.

An object of the -inventiohis-to provide a mining machine inwhich the feed rate of the .kerf

particularly toan im roved hydrafulic control syscutting mechanism is automatically adjustcdlto compensate for the load thereon therebylto lprevent overloading of ther driving motor forsaid kerf cutting mechanism. r V

Another object of thefinventionis to provide an improved hydraulic control system forja mining machine inwhich hydraulic ,meanslare pro;

'vided toefiecta ieeding oi the kerfcutting me Cl' i -i V anism in which .the rate of liquidsupply to the hydraulic feeding mechanism is adjusted in laccordance with thecurrent fioW inthefdriving n otor of the kerf cutting mechanism to prevent'overloading of said driving motor.

V A'further object of theinventiqn to provide an improved ,power operated hydraulic control valve. 7

Still another object of the invention is .topr'oyvideo. solenoid operated hydraulic control valve which is adapted to control the rate of fluid flow therethroug'h in accordance with the "current flowing in an electricalcircuit'.

Another object of the invention is ato provide a combined solenoid and mechanically operated st amcre ms hydraulic controlling valve {adaptedto y'ary pm;

gressively the rate therethrough. V 1 a Other objects of the invention will appearfhereinafter, the novel features and combinations being set forth in the appended d im s. In the accompanying drawings, Figs. 1, 2 and 3 placed end'to end y h qe t Sy tem f i i .9 \.a, s t 0 a1e y tional i w ofiapizlo F 1 i aseq i el n w it u QtFiE- n s n i w Fig.5 125s aisectiqnal V e taken on the linel 2%; I o 9 ink n i it 11; the 9 he a tak n ofi'fthe line 11a.

F 5 ass t a view taken n' the 1 I5 of'Fig. I4 looking 'in th direc nflor row d al sllQ ihs the enus; e a nti mfihansmttahi pe l ihsect oni Fig. 1.6" is an enlarged detail'vi'ew talgen on the maple 16f :thearr Fi i a mQ ifir or a bu mic e ip system showingf only thefportioii thereof "ch fi js r m th r li nt ol s t o :E'igifl;.'\ i F 1 is an enlar s se ti nal .eleiet qne view showing the structure of volume control valve 9';

1 F 41 is 1 l nler t w ewremain, se tion sh w. th e qtur ia a ust n mesh Pil t e. th contro sys m 0 fiq r ro raly smpl yed n the h raulic system .of

plan viewofagm'ining machine incorporating the features of ourinvention; V V Fig. 4 is adiagramn atic planview of the minmg cutswhich can be made thereby;

Figs. 5 and 6 areydiagrammatic elevational views of the mining machine showing severallyer} tical positions of adjustment of the cutter bar;

ing machine illustrating ,varioushoriz ontal swing- Fig. 7 isa pip l gcdiagram of the preferred form n of the hydraulic control system of our invention; Fig. 8 is a sectional elevational' View of thehigh pressure relief valve of thecontrol system of Fig. 7;

Fig. 9 is an elevational View of the preferred form ,of the automatic. ,volume control Yalveof the hydraulic control system of Fig; Tshowing its mqun s the in ma hi flam i setion; 1

1 31 lQ isaiQl ttn V r ves: Fi

Elsi Y. .M x V The mining machineherein disclosed constitutes an improvement upon the mining machine disclosed in the application of;-Robert Jeffrey .et .aL, ;-Ser.ial, No. 206,448, fi1ed..May$.6, 1938, .en-

.:.tit led Mining. machine, now Patent No. 2,263,759,

4 .dated' Nove'mher25, 1941.

It isxto be understood that unless a .contraryiact isindicated'ltlie struc- ;ture of the mining machine. of the: instant application follows 'the structure "of the mining ma- 'sumhing' operation; or a swing be effected either by swinging R s ect to the su lem ntal ram q by is JP chine disclosed in moredetail in saidalbovemnframe;tiiif'and turntable. j r

control the feeding forces supplied to the kerf cutting mechanismin accordance With' the load V on the driving motor which drives said kerf cutting mechanisrnij 2 1 7 Referring particularly to'Figs. L2 and 3, which together comprise a plan view'of the mining machine, andto Figs. 4, 5 and 6, which show the I mining machine diagrammatically, it will be seen? .i v that said machinecomprises a mainframe 3i!" V wardendof the platform is a two-way control including atrack'mounted truck 3i providedwithi wheels 32 adapted to ride upon mine ;track rails 33. r "f a Mounted upon thev saidltruck 3| for adjustment 'aboutan upright axis. is a'turnt'able" 3Q adaptedto be swung about said upright axis by -a pair gof f oppositely acting hydraulic Qpiston motors-35; Pivotally mounted "upon'the' tumtablet'fi for adjustment about a horizontal, axis 7 is a supplemental frame 36 formedbyahousing '31,ofjan'felectricaldriving motor '9! contained t thereiato which isri'gidly attached a gear hous- 'i ng 3 8 provided with anintegral and downwardly sloping neck tojwhich is journaled gear housing 39; that is, the motor housing 31, gear housing 'iiidhand neck carrying housing 39' are all rigidly attached together to nform the supplemental frame '38." Said supplemental frame 35; is pivot:

' ally attached to the turntableM-byjournal bearings to; so t th'elrear end or said supplemental Also forming a part of said supplemental is a pair of spacediarms or brackets between each or. which aims 4| and the'rnotor-housingtl' there is trunnioned the'housing'of a hydraulic piston inotor 42, the piston rod of which isjour 'naledto thefltu rntableiid. Thehydraulic piston motors iiare'adjustable to swing the supplemental frametd'aboutthe-horizontalaxis pro- "vided bythe journal bearings 40, thereby to ad-' just -the; elevation 'of ithe' forward en'd of--' s1aid supplemental frame iit. V

The rear end of the'inain frame 30 forms 'a supporting platform 'upon' which :is mounted anelectric-motor llif'which serves a number of ,the wheels 32 of-the truck (ii-to tram the mining :machine along 'th'e mine rails through an appro frame which there isan operators seat 6!! also adjacent appropriate drive including gears 63' to aidin the sumping action of-the mining machine par'-" ticularly when operating under difficult conditions or to anchor thefmining machine in the mine against retrograde movement.

Also mounted on an upright plate at draulic motor 45 to 'efiectthe sumping of the entire mining machine along-the track rails 3 3 The oiiterend of the neck housing 39 termi mates in and forms a turnover head'65. Mounted upon the turnover head 65 for swinging move ment about an axis which is perpendicular to the plane thereof is a kerf cutting mechanism "66 comprising a'fiat elongated cutter bar 6'; around.

which is adapted to move'an'endless cutter chain motor 9! ,(Fig. '7) contained'within housing 31 head 65, 12, pair of reversely operating hydraulic purposes-.' Said motor 43'drivesa'hydraulicpump H,

44 of-the hydraulic control system and also dri ves 5 priate gear trainincluding clut ch shifting Inech- -anism 45 which is adapted also to effect a driving 7 connection from.= the hydraulicmotor ifi to said zwheels Bite effect slow speed sumpingof the entire. mining' machine while cutting a kerf.

' v-Tha't is, theClutch shiftingxmechanism 45 in icludeslaishiftable clutch member 41- which isr operable fromtoperating handle 48 through a gear train including .pivoted shaft 49, rod 58, bell" crank 5 l :rod 52' i and l bell crank rshippera. 53 to "efiect a-drivingiconnection to the wheels 32 by way ofreduction' gears 54 either from ithe electric motor 43 when: operatingat a high'speed during tra-rnmin'g; or from the hydraulic motor '46 when operatingat a low speed during sumping. W Also mounted upon theplatform-55; is an electrical; cable reel mechanism 56 which winds in and pays out the electric cable for supplying cur- 7 ent a nmm motor 43 and which is driven' by I drive mechanism: 51 includingta control clutch 58 fope'rablfromappropriate operating mecha- .jn srnsinc i n'gf hand1e"59.' J 11 Itis to benoted thatth'e operating handles 48 through appropriate'drive gearing which extends through the gear housing 38, neck housing '39 and turnover headl65, It may be'stated that j the sole function of the motor contained within housing fi'lris to drivethe cutter chain 38 of said kerf cutting mechanism 66.

To provide for controlled swinging movement of the kerf cutting mechanism GG about its up right pivotal axis withrespect to the turnover piston motors Ellis provided; the cylinders of which motors are pivotallyattached to arms which form a part of the turnover head '55; The

piston rodsjof said motors Hlar'epivotally at: tached' to'an operating bracket 12 which is rig r idlyattached tothe cutter. bar 131. It isithus; manifest that byalternate'reverseioperation V the tw tOK'S UTFQ the cutter bar, 61 may. b t

swung initsown'plane' inireverse directions. a

To provide for, the swinging of the cutter bar a S? in a plane perpendicular to its owngplan'e,

particl f ilflyo softhat said'cutte'r jbar @l may be .horiz 'ontaily positioned, .forf iexample in anyiofj the positions illustrated'in'Figs; 5 and'fi ofthe drawings.- for different, positions of adjustment of the supplemental: frame" '36, said cntter ,bar 61 i j I is'pivotali'y"attached to the turnover 'head' 650d ahtransveree axis which isfipar'allel tolthe plane of said cutter bar! To eiiect' swinging movement of said cutter bare! transversely of (its plane there is mountedon theturnover head 65 a hy draulic'piston motorl3 the pistonrod'of which is ttached to a sliding head 14 to which are connected operating arms 15 attached to opposite plates it which at their bottoms form a vjournalupon which the previously mentioned-' bracket "52, is jjournaledjjfor swinging movement and which acts tosupport the keri cutting meche.

anisrntfi fr'oin the turnoverjhead 65. jIt-isevi "dent thatexpansion and contraction of thehydrauliopiston motor .13 will therefore produce a swingingmovement of the cutter bar 61' inian the forant war arc iperpendicu'lar'to itslown lplaneilliltris time. toibe noted that the cutter e imcl'ianism 5 6 :may;

beadjusted fork swingingmovement withirespect posedatr'a right angle withire'spectto each otherz To provide for the turning over of the; head 6-5 "so that the .cutter. bar Bl may be adjustedlto a bottom cutting position, as illustrated fornex ample in Fig. dot the/drawings, or'toa top *cut-:

ting position; as illustrated for example in; :Fig;

5 of the" drawings, .or to vertical or intermediate positionsf-on either side or the :longitudinaljaxis of the neck housing 39, the said neck hou'singfifi isxjournaled on the aforementioned integralsneck of l the supplemental frame 3fisandtisliprovided withmeans for rotating it. throughzalmos'tjgbut.

not quite, 360 degrees,"including-fa:rotaryitypepf hydraulic .motorll (see Fig.12)';which is adapted to rotate the. lneckihousing 39: through. appropriate Egearl reductionl mechanism preferably in cluding wormgearinggm 1 g l 1, 1 ,v i It may-be statedthat-betweenthe neck andits housing: telthere is a stop meansrwhich prevents 360 degreesof rotation butwhichspermits the,

adjustment loft-the" cutterrlbar 81 l to i any of the aforementioned positions. l

' To provide for the flower hydraulic .fluid to the hydraulic motors 7i] and 13 which, 'of course; rotatewithwthe turnover rhead mechanism v65 and thus" rotate with respect to; the usupplementalframe. 36, vfiexiblethose hydraulic conduits :18 are provided which wind upon winding reelfle which is. drivento rotate with the a driving cablelilll. V r t, it mayadditionallybe pointed out that mounted on one side .of the gear housing 38 of: the

supplemental frame 136 is a four-way hydraulic control :valve 8|. including four-"slide pistons which slide...pistons are individually controlled by four operating handles 82 (Fig. 2) positioned at'an operators station adjacent the rear .end of the supplemental'irame 36rand attached tocthe motor housing 3].: There is one handleilZ for operating each of the pistonsofthe four-way valve-8i.

lit-maybe statedithat one of'saidhandles and azwaspreviously pointed: out; 1 it-ci's; desirable:

' to'tregulate? automaticallylithe' feeding: movement.

of the kerf 1. cuttingrmechanism Strands-this is preferably done in inverse proportion to the'am-n pere loadpn theizdrivingm otor 9| (Fig. 7.) CD11? tairied. within housing 31. o It is alsoxpreferred' thatjrthis :inverse proportion be limited torless thanxtheentire range of ampere variation. In practice, the'imechanism; is preferably' adjusted so that theaicutter mechanism isdrivenat full speed until the current reaches approximately 85% of its/full load'rating, whereupon'the .feed

rate oftherikerf cutting :mechanism is progress sively decreased as the current of the driving motor increases until it:is finally-shut off .at.-ap-.

proximately l15 of'its'cfull rated value. :It vis,

of. course, to be-izunderstood .thatxtheaabove is merely illustrative of the preferred range and the range maybeextended in either direction to any extent;desired.- a .1 f a: l l

It is, of course, evident that withnthisrauto-lr matic system ithe'kerf cutting trnechanism is operated-at theemaximum rate possible without uri- ,desirable overloading of'itsdriving motor 91,

neck housing :39 .by' i oneof said slide pistons is individual to the two a motors iii, another individual to the:motor 13 another individual to the motorr'l'lsandranother individual to the motors 52. In other words, motors d2, ll, "it and :13 are-individually controlled by the. handlesi82 lwhichucontroliiidividual pistons of the four-way valveal; t." r It'may also be mentioned that :the previously mentioned two-way control valve 64 which is valves one of which isindividual tozthe hydraulic The apparatus which provides for; this which is thermotor in housing '37., so that when easy cutting'iszencountered, thefeed rate is in-- Y creased and. when hard cutting is encountered a the hydraulic .contro'l system.

Referring first to, Fig. 7 of the drawings, itzist to tbe. seenwthat the hydraulic: control. system comprises aatank or reservoir 85 for the hydraulic fluid or oil from which extends a feedpipe :86 leading to four reversely connected valves 87 interconnected to the hydraulic pump M from which valves 3!? there extends a pressurepipe'or conduitlfifi; Thepvalves Glare so connected that thegpressure :in the; pipe jiflizis :always positive regardless of the direction of rotation of the re .versibleipump M. .-In this connection it maybe r stated that driving electric motor '53 is ofthe reversible type sothat .the mining machinegcan carried bythe rear 'platform55 has two "slide motor #6 to ,control the sumping of i the entire 4 mining'machine; and ,the other of-which is individualto' the hydraulic piston m0tors 35 for swinging the. turntable 34, the latter of which is controllable from two positions, one of which is adjacent the control station wherehandles "82 bebtrammed in reverse directions and consequentlythe pump Mis subjected to rotation in 7 reverse directions, as shown in Fig. 1.

The pressure pipe 88 leads to and through;a

pressure relief and" by-pass control valve89', the

detailed structure oi%which is disclosed in .Fig. 8

ofetherdrawings, :and' hereinafter describedin'full areilocated by Virtue of LhandleBS. (Fig; 1,) the a other of which is controllabledrcmthei position near ;the operators :seat Bil by handle is desirable because during tramming 'of' the mining machine throughuthe mine it issome-F' timesnecessary to swing the supplemental frame on the-(turntable 34, particularly While, rounding curves in themine. All of the hydraulicsmotors iale' oontrollable from the pperators station adja'cent thehandles 82, for this is the normal position of an operatorjwhile-themachine is cutting 184. This detaiLueFrom 'saidipressure relief .valve 189 the pipeilli leads to the automatic volume control valve;.!lfi, :the structure of Which=is ldisclosed in full i'detailc'in' Figs. t9 l to 16 of the drawings,and Whichris one of the important features of; our in vention. 1 1

' (Asia: general description, itmay be statedthat the automatic control valve 90 is operative to control-the volume of :fiuid deliveredto the op-- erating hydraulic motors of the hydraulic system in accordance withthe .currentfaflowing in rthe electric motor contained 5111 housing 37 which =is illustrated at 9l .in Fig. v7 of :ZLeadingirom .the automatic control ivalve 9llzis the drawings.

trol; valve 6d. The two-way control' valve; .764 'is effective to control the selective feedinglofl'hy 'draulie flu'idiin reverse directions tofthe' thy; draulicpistonmotors 35 andilto thermry hydraulic motor 26; there being, of course} an in:

dividual piston tor the two:motors:35 on theone ghahdand the motor 46 on the: other; .11 i

ltmayi be stated that, as describediin coni-i.

plete detail-inithe above-mentionedpatent of Robert KxJeffrey et al., 'the'two motors 35 and 7 pressure pipe orr conduit}! which I-delivers hydrauli'c fiuid.under pressure tothe two-wayicon assanr fluid conduit during-this swinging motion 19.;

pivotally mounted packed bearing I04 is provided I which fdrms: continuing .paths leading to the motors J Il for various positionsof adjustment of the. cutter: mechanism 65' with respect to the; a

the single motor 56 are capable of ioperationLat.

the same time or individually due to theparticu- I lar c'onstruction of the control valve'B Ii :There 'is provided'a return pipe 93iwhicn dey livers excess .:or seepage fluid'from control'valve Bite the reservoir'85. A return pipe 94 isaalso provided to return hydraulic fluid from the bypass control and pressure relief valve 89 to the reservoirtfi. V 1'; a i Y. L

=It:may also be; mentioned thatleakage drain pipes 95Iand lare providedxior the motor 46 and pump 44, respectively, to return any excess fluid, such as is received due to seepage past the bearings thereof, tothe-reservoir 85 by Way of junction block 98; and return pipe9$ having two branches provides a return conduit from tworway'valve 54 to junction block 98.

That portion of the hydraulicqcontrol:system abovedescribed which. is to the lowerlefthand side of the line 99 in Fig. 7 of the drawings, is

stationary with respect .to' the .main fra'me of the mining-machine m'ent with. respect to the main frame andis v The portion of-the sys- 7 tom now to .be described is mountedfor adjustl all'mounted on theplatform V and therefore is carried'by the supplemental frame 36 or some 1 structure'which is attached to move therewith.

mExtending to the four-wavcontrol valve 8| is a pair of flexible hydraulic fluid sconduits or hoses itil'an'dxlfll, 'of which the former is a pressure'hose leadingfromthe valve Glandthe latter'a return hose which leads to theju'nction block and thence to'the reservoir 85. '.It may be stated that pressure is delivered to the'hose i o Iflfi from the pressure pipe SiiZ without regard tothe position of a v two-way valve 84.. Said conduits'or ho ses I01! 1 and ,IOI lead to and fromjthe four-waycontrol valve SI which is provided with f our individual I any of the slide valves of the slide valves as above set :forth, on of whichis operated to control-the motor ll, another of which is operated to control the two motors 42 iniparallel, still another of which isroperated' to control the motor I3 and'the fourthpof which is operated to control the reverselyicon'nect'ed J'Io provide 'for the floating of the :cutter'bar Ii'iv omits-pivot, when positioned. in a vertical plane which is desirable for the cutting ofverltical-kerfs while the mining machineis sumping alongla curved mine track, a by-passwalve: I02 interconnects-the conduits leading to ,the hy-' draulic' piston motor 13' which in cooperation with an equalizing valve I03, also connected between said conduits, permits the floating of the piston in said motor .13 whenever valve I02 is open. As above; described, the'reeli lfiprovides-for the rotation of the. hydraulicpiston motors Ti! and 73 with the neck housingl39.

i It is also: evident,. of course; that motors I0 mustswingiabout the axisof the turnover head which is parallel with the plane of the cutter bar 6I;' To: provide for the continuation "of the i- Referring particularly-to Figs. 9 a 1 in 1 clusivel of the-drawings'l'it is to be seen that,

the automatic'rcontrolvalve '90 comprises. a main casting IG5Lof'non-inagneticimaterialwhich has an integral i downwardly lextending cylindrical 1 a portion Mei-formed with spaced integral flanges ifllfllm upon which cylindrical portion 106 and} I 7 between: which flanges lflljand I08.is mounutedi,

ihsulatinglcas'ing'llfl. i i I Removably attached to" the an operating solenoid I119. contained Within an terial which has {a bottom integral flange ,I4 1

by which it isjattached to:castingI05 :byiscrews i I48, sealed together by seal'wires I49 and which is provided with a central jlongitudinally extenda 7 ing cylindrical bore H2. Substantially midway of the casting I II" is a chamber, orifice or pas-1 sagewayjI I3 which is formed by the bore H2 ex v tending through a centrally disposed web H4:

Above the web H4 there is a circumferential a port H5 communicating with the chamber H3 7 and provided withiathreaded opening H6 to which is threadedpressurepipe orconduit 88.

i'Itlis thus manifest thatport H5 is the inlet Y or pressure port for delivering fluid under prese sure to thechamb'erporifice' or passageway' II3 which, it may be stated, is adjusted as to effective size so that the pressure drop across the same: regulates by-pass control valve -89, as

hereinafter described, to control: the volume of fluid flow delivered to the pressure pipes 88 and 52 anduthen'ce to the'hydraulic'piston motors of the hydraulic .control system; The'structure 0t this port H5 and theconnection .to it is illustra-tedin-detail; in Fig. l2 of the drawings, Di-

rectly below'the web II Irthere is a circumferential" port I I'I' communicating with the chamber r H3 'and'pro'vided with a threaded opening to which .is threaded-pressure pipe or conduit 92. w It is'thusmanifestthat the'p'ortI I! is the out- I let or ereceivingiport" "for receiving fluid-under pressure ,frqm: the.chamber,' orifice-or passageliquid flow past said upper portion I20. The central portion ofjthe piston 1II8is formed as a shank I22 of reduced diameter which is norof mallyi positioned centrally "of" the chamber I I3 thereby-providing a maximumeffective-openingn A ofgsaid chamberv I .I3 when the valve 90 vis in normal position-of a'djustmnt ".LDirectly below the shank I22 is a generally 7/ 'cylin'dricalportion I23 of the piston-'Ila'which p is provided with oil-seal grooves I24 to restrict;

thGifiOWfOf Oll through the lower portion 'oflthe bore H2? "Extending downwardly from Ythecy- 'lindrical portion I23 is a'shank I25"which,'at its? bottom; ispivotallyattached to a-p img'e'r 1250f magnetic material by alooseconnecting f .7 pivot pin I21 which plunger extends downwardly into a central opening I28 in jthe'castmgIIIi toporthecast mg Ifi5 is'a*va1ve castingaIH of non-magnetic ma.-

within which opening I 28 I is a: helical; spring @I of. the tapered portion 3 the upper jen-d wof which abuts; angintegral flange of the plunger I and the bottom of which rests. on; a I led e I39 formed: in; said opening, I 28.

Elie opening i 28 isprovided with another ledge 5.31 which "stops downward movementof the plunger I25 under the influence oigthe solenoid It is,r of course, evident thatathe spring 129 @urges the piston:.II3' toathe maximumv valve opening position as illustratedtin' Fig. l4 of the drawings, and that current. flowing in the sole;-

wardly'against the action of thespring I29 which,

after" a I predetermined movement, progressively reduces. the eifectivesize of the chamber, orifice on ahorizontal plate-21sec Fig. 9); by virtueof aflange Informed as an .int e gral partpfcthe casting I 05, which flangeisattached to the plate .opening I281 I i o 1 --In the top of thercasting H Ithere is formedta or'passageway 113' by the progressive: movement II 9 of'piston H3 there,- through. 1 1 1 c c g V Itis'further manifest, that the effective-size of said; opening or passageway H3 is inversely proportional to the amount of current flowing in the solenoid I69 once the tapered portionllfiiof piston I IS has entered said orifice or-passageway M 3 As previously suggested; in "practice 'it is preferred that a current of'substantially of the rat'ed current for the motor 9| will be required' before any-appreciable *reduction of the effective size of "chamber, orificeorpassageway :H3 is effected, and that said pa'ssagewaywill be completely "closed 'When the current reaches approximately of the rated'valum' the com plete closing, of course,-being*e1fected whenever the upper portion IZEI of said piston H5 enters the orifice or passageway M3, for it substantially completely fills it. n V V I To provide for the manual adjustment'of the automatic control valve 99 so'gthatan operator may vary the'actionthereof, to reduce the feed rate but, preferably, not to increase the feed rate, Without regard to its; tendency to operate auto-,

matically, said valve mechanism is provided with manually operable mechanism including an operof jsaid platform 55 so that said; handle 1 3;

for'wardlythrough a slot an uprightplate. a I 45 readily operable by theaoperatorwho controlsithe valves and 3 I.;. from: handles I 83; and? 2 'spectivelyfif j As seen by reference to Eigii thedrawing s,

the 'central portion of the automatic control valve I 90, provides .a-chamber M6 which will be filled with hydraulic fluid at all times, due principallyrto seepage;.whicl1 hydraulic fluid will act as a-lubri cant for the moving partsirthereinand in; the

chamber VI5Il -which: 'comrnunicates with .;j the chamber:- I ifiiby' way of: passageway L5 I. Excess hydraulic fluid is drained from the; topofythe chamber I5ll:hyprevio,usly mentioned; return rapip e "93$ (see'Fig'. 13) *1 t Tot'dampen 'somewhat the action of thepiston H8 we provide in association with theupperpon tion l 'I Zhthereoia dash-pot the structurei of v which is best seen by reference toFigs; 14 and 16 of the drawings. "Said d'ash-potis formedzby a, cylin 'drical bore .152 in the toprorasaid upper portion ating' handle I32 which is pivotally'attached to a stub shaft 133 supported upon, the valve casting III by a journal bearing- I34 and journal bearing I 35, the latter of which is formed in a removable cap I36 which is attached to'said' casting III by after pointed out; If desired, collar I41 maybev 12o into" which projects a: piston I53 fwhioh- 'is' slightlyless'in; diameter thanthe cliameteriof the bore I52, said piston'l5'3rbeing formedas-aanj integral portion of aplug I54 havinglenlarged portion Iiie which is adapted to extend into'iand close the bored H2 formede-finithe: extremetop portion of'the casting III. The plug I54 addie tionally has a top" cylindrical: portion I56 which :is rigidly attached to a'renrovable topeplate I51, for example as by having va press 'fitl therewith,

casting 'IIlI as'byrscrews" I58. p To provide a3=contro1 pressure conduit which plate t5] .iS-IEIIlOi/Tfllblfi attached, to the leading from-the valve'm to the high pressure relief: valve '83 which is responsive tothe' pressure in the pressure pipe-or conduit 92" which, of"course,l is'the 1 same as the pressure" in-the port I I'L-Ii provide a conduit which'is formed" by a vertioalhbore: I159 see'n'by reference t'o'Figs. 9 and 13 of the'drawings, the bottorn of which communicateswith-said port I? The vertical bore I59 communicates witha transverse bore It!)- towhich is connected ta 7 pipe or conduit I6 I asseenby-refer'ence'to Ward direction to reduce the feed rate aLs-hereincommunicates with threaded plug I 62-. I

Fig. 7 "oft'he drawings, leads to the pressurerelief valve 89) As illustrated in Fig. 13*of the drawings; the top of thevertical" bore I59, which chamber I50, is'closed by a Referring particularly to "Fig. 8: of the drawings'; it will be seen that the pressurerelief and rigidly attached to shank I25- inwhich" case the,

feed rate may beeither increased or reduced manually, and this may be'either with or without the automatic control provided bysolenoid lim- It may be statedthat'the-forces acting on-the piston H8 by virtue of thefspring Iifian'd the' solenoid? IBQ'are relatively small as compared with the" strength of an operator'and may be at the maximum-of the order of fifteen; pounds; Consequently, an operator'will have he difli'cultyin' ad justin}; the piston H8 manually by the handle,

I32 without regard. to the tendency of the auto'-- maticmechanism to adjust said piston Me.

It may. be stated that the automatic control valve 99 1s mounted adjacentthe forward lefthand -portion of the platform 55, fas' seen by reference to Fig. l of the'drawings, and-is 'cafried by pass 'control valve 89 comprises a "casting or. body I 83 provided with a central "cylindrical "bore I6 1 withinwhich is ya control pistons'Iliii moved downwardly by arelatively weak-"helical spring I56 whieln bears against a closure plug 151 for thebore [645" i *lnf'thebottorn er the casting :es is. itemsversely extending passageway I 68 through'whi ch thet'wo extensions of the pipefiie'are in direct I Communication. At th'ebottom ofthe-boreifi l and at a position generally surroundingf'the pie"- ton ltd-when the latter-isinits normal position, isa chamber I69 which is connected to. return pipe Qfl bya passageway I189 ZAIbOI'E' I II-provides a communicating passageway. between the pas sageway Pitt and the-bottom of bore. 1564 thereby to subjectithe bottom; .ofzthepiston-Ifii to the as L , tresmiem the passageway lfis whichgof course,"

-2334771 I x V 46] which-maybe co nectcdtodrive said wheels 32, asaioredescribedfi During any sumping 'operfis-th'e" same as thepressure in the pipe 88. Bore l f I I I also communicates with a pressure gaug I12 (see Fig. 1'7) by Way of conduitllS Which-EpresSure Y 'gauge'i'lzIof course; measures the pressure in the ressure conduit 8 8 1 ation the cutter-chain 68 of thekerf cutting- V mechanism 66 is, of coursefdriven byj'the electric motor 9l -which is within the housing 3'LMAs "1 previously mentioned'the electrit: motor 9| does not drive any other-portion of the fminingma i above that assumedby thepistonilfifi'duringany operating condition; and the passageway {I19 which: leads @to the drain pipe,94,;is -apassageway lit eauinefto chamber-115 which inturn leads 'topassageway 116.v An "adjustable =bal1 check. valve' I1] is provided in chamber' IIB and will release upon" a predetermined pressure in the 1 As'fwas above pointed out, the pipeforconduit l6 communicates the pressure in the pressure pipe Brand port H1 to the bore I64. Consequently, valve 89 acts as a high pressure relief 'valveinthat whenever this pressure becomes ex- .cessive at any value which may be adiustably determined by the check valve HT, an example chine.

. During the performance 'ofja sumping .operationasabove described, the current new in rthe" automatic valv'e controlmechanism 9S. Said I valve control mechanism 90 is preferably so-de-- f signed andiadiusted that until the current flow 'of 'which is 1200;pounds per square inch, the

check-valve" ITI will operate torelieve this'presthe return pipe 94. The flow; of. this high pressure fluid 'from the conduit i6! i'ntofthe bore-164 is througha passageway I18 which has'ajvery pressure drop "Whenever the fluid beginsto flow through saidpassagewayfllll. V

l Afterithe. ball valve 111 has cracked and the high pressure flui'd begins to how to the return pipe-fa l the pre'ssuredn the bore I64 above the piston- I65 will fall belowthatonzithe bottom oi said'piston I65 due to said pressure drop through passageway H8 which will result in the fluid under pressure on the bottom of the piston 65 moving it; upwardly against the action of the weak spring I 66, to provide a direct communication-between the bore 11 I and the passageway I10 by wayof'chamber 1691' This, of "course, will pro 7 -l vide a direct communication between the condu'lts 88 andM thereby providing-a direct return pathior high pressure fluid in the 1ine88 to; the return pipe'fi l. Whenever: the pressure'in the valve 'l'l'lwill close and the parts of the high pressure relief valve 89 willbe returned to their normal-positions as illustrated in Fig-100i the drawings, Said 7 valve 89" also has an important restrict'ed area'thereby' causing an appreciable pressure pipe 92 isjreturned to'no'rmal, check -function as a by-pass valvaas hereinaijter ex- 'plained. Y -1.Byreference'to-Fig. '7 of the drawings, it is to behoted that the solenoid H19 of the automatic 7 valve control mechanism!!!) isconnected in series with the-armature of, the motor 9!. whichdrives' --the kerf cutting mechanism, .As a consequence, l the automatic control valve 9 3 is adjusted inaccordancewith the amount of current flow n isa'id (gr 'kerfoutting-drivingmotor 9|.

. In the operation of thetmmmg machineiincorr 'porati'n -ith hydraulic control system-above dein said-motor Si is approximately 85% of itsnortrial or rated value, the automatic volume control mechanism of valve 90fwill' be in its normal;p0-; J V

sition, as illustrated in Fig. 14 of thedrawings,'-

under which condition the'system operates to de;

'liver a full volume offiuidto whatever hydraulic motor is being operated which, under'the condi v tions now {being described, isjthe 'sumping. mo-IY.

It is, of course; manifest 'thatl before any kerf cutting operation is tobe performed, the cutter bar 61 must be adjusted. tojadesired, position. 1

This may be done with the motor 91 ,de-enlergized,

or it may be done with said motor running light,

under which conditions-the. automatic volumecontrolvalve Sdisnot in operation and ini'no V wise-acts to restrict the volume of liquid delivered r to any of the hydraulic motorsg'lfhis preliminary 7 adjustingof the cutter bar will probablycall into I play practically all of the hydraulic motors in' eluding motors 35 for swinging the turntable,

motor 46 for moving the mining machine inits entirety forwardly or rearwardly at a slow peed,

hydraulic pistonmotors 42 for adjusting the 'sup-' plemental frame 36 ,about its horizontaliaxi's with 5 I respect tothe'turntable 34, hydra'u1 ic piston motors 10 for swinging the cutterbarl 61' with re-v spect to the turnover head 65: in its' own, plane,

hydraulic motors 13 for swinging saidcutter bar transversely of or at right angles to its own plane,

and rotary hydraulic motor Tifor turning over ,thehead65, neck housing and all parts rigidly I attached to them In the performance :of "the drive the continuous cutter chain 68. {The sump,-

ing' operation may be performed in a horizontal j plane whichplane may .lie anywhere between]? the top or roof of the mine room, for exampleas I illustrated in-dotted lines in Fig. 5 of the draw j .ings, and the bottom or floorofthe mine room, for example as illustrated in the full line post-i V I tion at the bottomsof Fig 6 of the drawings. Furthermore, a horizontal sumping cut may be made atany'intermediate position between the.

twoextreme positions above mentioned. I

1 In' et wide entry such as one-where.

tance between. the ribs is approximatelyequal to twice the distance from the turntable axis'toithe. v V ,7 outerend of ,the cutter bar, a continuous; horie 3 zontal arcuate cut may be made on the turntable;-

' aidsfas-illustrated by the semi-circle in fulliline j in Fig. 4. 'In entries .not so wide the successive" ,arcuate horizontal connectingicuts illustrated by I the dotted lines in Fig. may be made,v the turn- I table and supplemental frameSB being held in;v I

adjusted position relative to-thehstationary truck 3| for each such successive arcuate cut. The

feed "of the kerf-cutter on the turntable axisis sumping operation v as previously mentionerl'it is, of'course, evident v that the cutter mechanism 66 isin operation and -L driven by the electric motor 9! in housin'gil to;

the dis- .1;

effected by means of.therhydraulic;motorsjii; .35

and the horizontal kerf; font; is .on arelatively long radius; Therfeed;ofitheakerf cutter onqits own pivot is: eifected by means of the; hydrauli-cismo- ;..10. and the horizontal kerificutgis .onra shorter radius; r

aaamm In; narrow entries it; isgpreferredi first toamalie a. 'sumping cut' by traction: feed along the: mine track. Ilhat: is, v the whole machinetis moved: along the minetrack at feedingspeed to cause the-ketficutt'er; to. cut a kerf' rectilinearly parallel; to the mine track in. continuationv of one of. the, ribs of the mine entry. This is-followed' by a-rcuate feeding horizontally either on the turntableaxis or on the pivotal axis of the-cutter bar while'the truck is-stationary on the mine. track. Finally, a rectilinear withdrawal cut is made by; traction feed to finish the horizontal hert along'theopposit-e rib ofthemine entryi; During: the rectilinear sumpingaandwithdrawalzcuts parallehto themine track, the cutter bar is i hold. rigidly connected to.

rigidly connected to. the truck 34;. Horizontal 'kerf'smay; be -cut; between the ribs'of mine; entries .of: various. widths at any elevationi between; the .fl'oor andtheroofu' I Vertical or shear kerfs maybe out between thefloor and roofvofmine entrieslofqvariouswidths anywhere between the; ribsgthereof. v.For: such shearing cuts .the cutter baris adjusted. to: a. vertical. plane. by means. of; the. rotaryhydraulic, mo-

tor It and; the shear kerf completed by rectilinear sumping and withdrawallcuts parallel-to the; mine track connected by 'arcuate' cutseither on the pivotal. axis ofy'the cutter bar-oron the axis of the .trunnions; 40.; 40. (Figs. 2, '5, 6),. the. sumping and, withdrawal cuts: beingefiected by: traction feed or by'movementof thewhole machine along the mine. track at: feeding: speed: and the upright arcuate. cuts being; made either; by -ther motors m, 1!] or .themotors 42 42.;.w1 rile the truckr is stationary. on the minetrack:

the-supplemental frame 36: andathe latter is held independent of thepressureetwhich the hydraulli'c fluid is flowing-to theoperating-hydraulic mo- 7 ton] As .was above set. forth, there is a prede termined positionforthe piston H8. of'saidcoIrtrol valve 90 for. each current yaluebetween 85 .percentnanda 115 percent of the ratedloadof motor: 95!; 'Q'Ihis, of. course, means" that; orifice 11:3. has a: predetermined. efiective size for. every current valuebetweenfthe mentioned limits. This orifice. H3. is. so arranged that the pressure drop. across it is proportional to its. size and the volume of hydraulic fluidflowingthroughitand entirely independent of thepressure of. the hydraulicfluid. This drop in pressure across aorirfice: I.l 3.1is, of course, transmittedto piston'i65 of valve189:and employedto control the by-pass- .ing ofhydranliu fluid thereby. That. is, the hydraulic fluid-pressure import H is: the same as the pressure below pistonlBS, and. the hydraulic fiuid pressure inport Mlis .the sameas the pres- "sureabovepi'ston. I65. The top ofpiston ifiE also has. added: to'the .hydraulic':fluid pressure, thatz'of under the influence of a load on motor Sig-as Also for: adjustment purposes: preparatory. to

Keri-cutting; the cutter bar :may :berswung'zabout its pivotal; connection to the turnover. head: 6.5 by

hydraulic piston motors 1.0-. or: about the hori-, zontal 'pivotaL connection between the supplemental .frame. 36; and the, turntable: 3.4rprovided bythejourhall bearings 'underithe influerrce of V I the hydreurlio1pistorrmotor ;42;v i I s 7 It. is-to, bei noted; that. said; hydraulic piston motors 42, at, in andiie are alll'lofuthe double 1 acting type so that they operate positively .in. reversedirections: byl'reversing'the direction of flow of the hydraulic fluid thereto.

It is. to be particularly: noted-"thatiwhen iany of the hydraulic piston motors. such as motors 35, 42, 11!; E3 or lliare inoperation, andlthe electric driving motorQ I which drivespthe-kerf-cuttingmechanism. 65 is in operation, and alcerfis above describ'ed,- this full. volume of hydraulic fluid when flowing therethrough produces such a pressure dropthat the pressure on" the bottom of piston 165 is greatly'in excess of that on its top ywhich causes it to rise and allow a portion of the fluid to by-pass from conduit 88,- bore lH, chamber'169, passageway I10 to return pipe 94.

In actual operation, this'piston I65 automatically operates to by-pass just enough hydraulic fluid tomaintain-the-flow "of hydraulic fluid through orifice! 3 at a valueto maintain the piston Hi5 in a condition of equilibrium whereby itby-passes just thezrequired amount 0f hydraulic fluid at all times; delivering the rest to the hydraulic motor in operation to feedthe mining mechanism at a rate. to keep the load on motor llllwjthin the above mentioned limits. Should the load on 'rhotor 9liincrea's'e atany time, the efiective size of orifice H3 is; of. course, reduced causing an increasedpressure drop thereacross which lifts 1piston.ifi5 higher to by-pass more hydraulic fluid, thus, reducingthe flow thereof through orificel-l 3 .andtto thehydrauliemotor performing the work until. said piston 165 is again in .a condition of equilibrium.

'60 actuallyibeing cutthereby. placing a load-on said 1 motor QLthe automatic-control valvefifltlseffective tolmaintain the-feed rateofithe; cutter n'iech anism 56 at a value such as to maintainthe current, or mother. wordsitheload' on. the motorist,

within safe 'limitsh i v If, during the'outting of a kerf the operator "desiresto vary. the-automati-oa'ction: of the-,auto;- matic volume-control: valv -an: to decrease the feed rate of'the kerf-cutting mechanism this may be done by hisoperating-the handle- +32 thereof, as above described} The-mode of control-over the-'volumeof hydraulicfluid delivered" to'an' operating' hydraulicmo tor-under-the control-of automati'c volumecontrol 4 7 motor doing; the work;

Iagaininia condition of equilibrium.

- Should the loadon motor" 9 decrease. at any time, the efiective size; of orifice H3 is thereby increased causing a reduced. pressure drop there- .across which causes piston N55 to :move down- Wa mly .toi'reduce the; amount ofhydraulic: fluid by passed, thus; increasing the flow thereof throughorifle; H 3 andtothe particular hydraulic As above, mentionedgthisi automatic action is independent. came pressure of. the hydraulic :fiuid. .I-Iowever, valve: 89; in. addition to this by-pass control hydraulic fluid; also" has the high pressure relief control afiorde d byTcheck-valve I11 as above described: The automatic volume control valve and by pass controlvalve 89- thus coop- I valve 90 is.-,of utmost importance and one .Of;it$ outstanding characteristics is that his entirely until said piston. I65- is V 'erate to regulate the feed rate of the kerfcutter Bier-of themini'ng machine to maintainlthe load Attentionis now directed'to V inclusive, of'thedrawingstin which there is illuson motor til within safe limits;

trate'd a modified form-of automatic volurrrecon trol. It istofbe understood, that the hydraulic system of Fig. l'lis the sameas the system of Fig.

; 'l. except'wher'ea contrary condition 'isfindicated.

In -general, it maybe 'stated,1that the, principal :difference is that automatic volume control'valve '90 has been replacedby other mechanismincluding automatic volumecontrol valve 225 and-mechanism for operating it. Y I

- in the systemv or said l'i thearmature cir- Figsr-l l and 19;

cult of the electric motor 59! has connected in series .with'it' 'a solenoid I'I9-With whichthere is associated 'aiplunger I89 which is connected '.to an' adjustable helical spring I8! by a shaft I82.

' Shaft I82 is pivotally'attachedto anope'rating- :lever I83 pivotedat I84.

1 fAssociated with thelowerportion of lever I83 is'a pair of oppositely positionedcushioning spring I "abutments 585, the detail structure of which is illustrated in Fig. 19 of the drawings; Each 'of said spring abutmentsltfi comprises a casing I86 carrying a stop EM, and within which is mounted .a' slidepiston I83 to whichis attached an. outwardlyextending contact pin I 89 adapted to contact thelever I83 after a predetermined pivotal movement thereof. Also, in the casingl86 isan adjustablecap I99 the positionof which maybe adjusted by adjusting screw I93. r

Between the slide piston I38 and the cap I95 is a helicalspring I92." Itis manifest that by adjusting the cap Illfi the tension on the; spring I92 7 may be varied thus varying the amount of current that must flow in the solenoid I19 to adjustfthe position of the lever I83; 7

The leverjiiZi-i controls aypilot valve I83; the

" structure of which is disclosedin detail inriazo han'd end of cylindrical'portion 226- of th'e'slide '-the motors 35, 42,425,?6 or13, the current flow in r of the drawings; Said pilot valve I513 comprises 1 acasing I94 provided with a central'cylindrioal bore I95 closed at one endby a plug J96 and havingthereinaslide piston I 9'? provided withan operating rod I98 which is attached to said lever I83 and extends fromthehore I95through a seal-' ing gland I93. Thepressure pipeBil 'has a branch 88 which leads to the] central portion of the here "I ,thereby providing hydraulic fluid' under D pressure'at this position. Leading Irom-the' bore 5 .I SE isa pipe onconduit 2M. .Forwardlyand re'ar'-, wardly' of the piston [9! are drainage ports which lead to pipe or conduit ifil which, in turn, is con:

nected to the junction' hlock $3 and thence to" Itjs manifest from reference to Fig. 20 of the drawings,=that with the piston I91 inits normal position, as illustrated, fluid pressure will not he supplied-to the pipe-ZEHllbutsaidpipe 23l is free to drain fluid to'conduit- 28L Howeven'when said. piston is moved to the extreme right, as

viewed in said Eig ZO in response to a predetermined heavy currentflow in solenoid ,I 79, conduits" 88; and NEE-will be in communication 3 through bore I95 to supply-hydraulic fluid-under pressure to said conduit 2% which leadsto automatic volume control valve mechanism 225.

--When thefcurrent" new iii-solenoid H9 is; below' .a predetermined value, pistonlill will be moved by the spring I 8! to the left, as illustrated in Fig.

17 of the drawings-t0 permit a fi'ow'ot fluidfrom The structure ofthe automatic volumecontrol 1 a valve mechanism QEEjsdiSclosedin Fig, 13 of'the' 7s 7 ,2 ,'ss4,77:1 p v drawingsand comprises a casting 225 provided, ,with ia cylindrical bore 221' which at 228provldes an opening, chamber,orifice or fpassageway formed in a web 229 with which communicates an inlet port 23l-having afthreaded opening ZS-Ljto receive pressure conduitor pipe 83;, The opening; 1 p 228 leads'to outlet port 232 provided with'threaded 1 H v openingtiit which receives pressure pipe 'or con- .duit 92. gslida'ble Within the bore 221 is apiston 2'34 having a tapered portion 235and'a cylindrical portion Ettprovidedwithoil; seal grooves 26'I.: shank'ZSB of the piston 234 connects the tapered portion 235 and'another cylindrical portion 239 which is also provided with oilsealgrooves' 240. Extending from the cylindrical portion 239' is a shank Z-tl around'which extends a helical spring 242cm end of which rests againstthe'cylindrical portion"239 and'theother end of which abutsa plug 243. A seepage pipe or conduit 2441s pro- 7 .vided to drain the boreZZ'lto the rightof the cylinder 239, as viewed in Fig. 180i thedrawings The -obvioussimilarityloetween; the structure of the piston234 of' Fig. l8'of the'drawings and thepiston IIG'of Fig. 14. ofthe'drawings, and the 1 cooperating parts including thesimilar chambers,

orifices or passageways H3 and 228, respectively,

make the mode of operation ofthe; automatic volume control valve 225 obvious: It is, of=course,

evident, however; that the va1ve'225 is not operated'directlv-by; a solenoid. but, on the other '1 -hand,'is operated from pressure in thepipelIlIl which is communicated to andacts-upon the left-- valve 2%, asviewed in Fig. 18.

The principal operations. of the hydraulic Sysa tem of Fig.17arein general similar to those of Fig. '7, though not identical. 1 The detailed operation is slightly'difierent. 'In the system of Fig. 17

whenever the mining machine is performing any 7 kerf cutting operation bytheoperation of ianyiof the motor 9 I ---fiows through thelsolen oid I19 to energize it.; Whenever this current reaches a predeterminedvalue as determined by the adjustment of the spring KL-and the springabutments [85,, which, for example may be percent of the rated load ofsaid motor 9|;pilot valve .193 is oherated'to connect branch conduit 88-'-and conduit 290 thereby supplying hydraulicfluid'pressuretd' actuate the automatic-volume controlY'valve 225, v 'Pist0n'234'is then movedtothe-rightesviewed "inFig. 18.0f the drawings, to adjustthetapered portion 235 .therebyreducing the effective sizeof 1 V I orifice 228-. through which hows the hydraulic fluid suppliedto the-pressure conduit-82 and to whatever hydraulic motor is performing the feed :ing operation of thekeri-cuttingzmechanism 6.6 This action will't'ake place untilthe by-pass valve 89 sufiiciently-reduces the flow'through'pipe 92 to reduce the feed rate. of the kerf cutting mech-fg;

' anism 56 so that the load on motor 91 is reduced} f ii for example, tor85 .per cent of its rated'load, whereupon pilot valve. I931 is returned auto-r5 .matically to its balancedposition with pipe "290] sealedby'the right handboss ofpiston I8? due 4 to thefact that the reduced magnetic pullion f plunger tail now equals the -pull .thereonduerto 7 spring -1I8I, which will stop: the movement of pis ton. 234 of automatic volume control mechanism 225 which will be locked in 'this position of see it 1 justment and; hold the piston 234 111 this position. 7 jIt is, of course, evident that continued variations in the load on'the'nfiotor at will causecontinned operations of the solenoid I39 with result 'ffl ing operation of the pilot valve I 93 either to p o},

duceanadditionaljdecrease in thefrate offlu'id flow to the hydraulic feeding motorortu increase said feed rate, depending upon the rate of current flow in the solenoid l-'l 9."; llnifshort lpiston 234 is moved by power imder the pontrol of sole- 7 noid l'!9,t o such a positionthattheloadon motor 9! is retainediat -a substantially constant value i between variable limits which may; be very close;

or relativelywide, such as from-35 perceutto 1115 f percent of its rated load,

To reiterate briefly, it is manifest that w th either of the hydraulic control systems oiiour invention the hydraulic motors for adjusting the a cutter bar Blto anyposition of adjustment-pre paratory tothe cutting of; a ,kerf are. supplied with a-maximum volumepfrohydraulic fluid; thus] 7 insuring their rapid movement to;.,- th'e desired positions of adjustmentuwhich;of courseggare efiected'without any load onythe kerf cutting mechanism or uponw-itsdriving motor 9 l since 20 these adjustments will be efiected ordinarily with the driving motor 9! Tole-energized, orunder any.

conditions, operating appreciably short :;of; its ratedloacl.-- I

Once a kerf cutting ioperationiis started'and throughout the continuous operation ofany kerf cutting operation involving the action of any of the hydraulic motors which are employed to adjust the.cutter bar 6! during the cutting of a kerf,

' the energy supplied ,togthe' driving motor 9l= of the kerf cutting mechanismxfifiiis employed, for

example, by feeding the current through a solenoid-to control in an inverse'manner the feed rate of the kerf cutting mechanismin accordance with the current flow in the driving xmotor J91,

in the system of Figlflghand inrthe'syst'em of Fig. 17 to maintainthe feed rate 'suchiaslto maintain a substantially constant load on motor 9| within a variable range.. z.

As was previously mentioned, inithelsystem of Fig. 7; it is preferred that theifiuid deliveryto the hydraulic fe'edimoto'r, whichever. one itmay be, is maintained at 'a maximumsvalue until-a predetermined load is placed on the motor- M which, for example, may be185 percent of its shutoff the feeding of the'kerf' cutting mecha- 'nism entirely. 'Ho\vever,;.;superposed uporiathis automatic feed control is a, manual feed control.

wherebyithe fe'ed'rate ofthekerf cutting. mecha nism may be taken overfifro-m the automatic t'o the manual at the instanL-cerof the operator'.-1: In the system of lithe fluid delivery rate to the 'hydraulicifeed motor inoperation ismaintained at a maximum value until the load "on motor 5! I'reaches. a desired maximum which, for

example, may be 115Hpercentaof its ratedivalue;

though any other setting may. beeifected..- Thereafter, the feed rate of the kerf'cuttingmechanism automatically adjustedvto reduce the loadon motor 9% for said kerfcutting mechanism and when'this load isreduced.toianyidesiredvalue, V v a r tsqwithout d pa TOm:.Ih.1 R an scope of the invention-asdefinedbathe claims .hereto appended, and We therefore wish not to be for eXample, toI' 85.percent of its'rated load,ior any other selected valuewthe feed .rateiof said .that the motor uinduly overloaded or oyprloadedato suchantexcutting mechanism,,said feedtrate is automatically increased until the loa d on'said. motor 9 reaches llfipercent of its ratedload, but nomore.

-g-; While ourimprovernents relateparticularly to ;,the automatic control of fluid pressure motor mechanisms v which 1 feed I the kerf cutter eith er rectilinearly parallel to the 1 mine track or 1 a rcuately on thepivotalaxis of the cutter bar or. on the axis of theturntable, it should also be noted 31:. is p t c s 5 asain n ei tent; as to} cause itjtohe overheated; or burned out. It has vbeen found in practice" that a pres;

sure responsive relief valve around the pump of a fluid pressuresystemfor lierf cutting machines 7 does not act properly to protecttl eputter chain driving-motor;

The systems of control shown in.theaccorm panying drawings; dependupon variation l of: the electric current passing throughthecutter chain driving jmOtOI" 9| tocontrol; a. b t-passing of a hydraulic j fluid in accordancewith a pressure drop across an adillstableorifice which isfindependent of the pressure of the hydraulic; f iuid, but is directly responsiveto the volume -of hydraulic fluid flow, an'd thereio'resuch: systems of controlare efiectivedo -act longbefore there is any tendency to;overheatthei notor 9L Moreover the, variatiopgin the volume fi 0W of the pressure mediu'myto the various hydraulic motors are gradual andextend overa wide range. i; In startingr aushearing out the operator may effect a slow startingfeedingforwardof the kerf cutter under control ofthe manual lever i 32 of Figs, 7, ;9 and, 10, independently of automatic control effected bythe current through the motor 7 in thatthe electricmotor '5 l for driving the chain 9A and the solenoid' l ;fl9;l, Thi'senablesjthe oper- :atorto workfthe kerf cutterslovvlyginto cutting a io after which th au omatic volum was takes over;the ;c ontrol, Q

it It will thus be seen that the eficiencyof operation may be, safelyrmaintained at a maximum cutter may be continuously and safely operated at its. full load capacity or any other predetermined setting, so thatwheneasy cuttingis encountered,

250 to be connected-to,the drainage pipefiiliy the rate of feed istautomatically increased, and when; the cutting is hard, the-rate'of feedis au;- tomatically reduced." Morecven. when nofcutting is taking place and the driving motor 9 l. is running free or is-notnperating, the rate; of feed'for adjustment of the kerf=cuttergrelative to the supporting framework, isiautomatically raisedto a maximum; If; the currentgtojthe motor. {it is, out 011 du in such ad st ents. of t heakeit awi cr, the spring lfil inFig. 17 moves thepis ton l8?- to the left, as viewed in Fig. 20, to1 permit thepipe move the ,piston 234: :to such} position that t e volume control valve 225; will'be in it widest open Y position, for maximum flow of the iiuid prejssure kerf cutting mechanisniis. not furtherire'duced.

medium totheadjusting motors. 1

Obvious1y.those skilled in, m n make various changes the details and arrangernent restricted to the precise construction h rein dis 7 closed; V

the current flow' through whereby the effective'size of said orifice-ism Havmg thus described and shown an embodiment of our invention, what we desire to secure by Letters Patent of the United States is:

1 Inapparatus oftheclass described, the comanaemia with a frame, 'of cutting mechanism mounted thereon, aj-motor for drivin said cutting mechanism, fluidpressure-mechanism for feeding saidcutting mechanism-a volume control valvef'o r controlling the rate of-fiuid flow to said pressure mechanism, means responsive to-th'e load-on s'aid motor' for adjustingsaid control valve and thereby adjust the Volume of fluid delivered to said fluid pressure mechanism to adjust the feed rate of saidcutting mechanism, and

means"operableindependently of said load r'e'-' sponsivemeans for adjusting sai'dvolume control valve whereby'the feed 'rate 'o'fsaid cutting mechanismmay b manually or automatically controlled. Y a

L 2; In-appara'tus'o'f the class described, the combination' with a frame, of cutting mechanism mounted thereon, motor operated mechanism for drivingsaid cutting mechanism, motor operated means responsive tdvariations of load on said driving mechanism toregulate the rate 'ofieed to maintain said lead substantially constant, and manual means for controlling said last-named motor operated means independently of" the load on said" driving mechanism to decrease butnotto increase 'the -'feed rate of t-he'cutting mechanism 'atthewillof the operator. p V

3; In apparatus of the class described, theco'mbination with a cutting mechanism, of hydraulic means for-ifeedingsaid cutting mechanism, a driving electric motor for said cutting mechanism: mechanismror feeding hydraulic fluid to said hydrauli-c feeding means 'includin'g a valve having anorifice through which hydraulic fluid flows to said feeding means; ir-ieans for adjusting the eff'e'ctive size of said orifice to a predetermined value for each value of current xfiowing to said electric motor which effective size is inversely proportionafto-s "d current, and mechanism fordeli'veringhydraulic fluid to said-hydraulic feeding means as determined by the" pressuredrop through s'ai'd orifice. 7

4.- Inapparatus" of "the'cla's's described-,the combina'ti'on with a cutting mechanism, of. h draulic mcans ior feeding fsaid cutting mechanism, a

dr-Wifig; Blbtfid motor for said cutting. mechaat p msm, mechanism for" feeding hydraulic fluid to said. hydraulic feeding means including a valve having an orifice through which hydraulic fluid flows to said feedingmeans, means for adjusting the effective size of said orifice including a tapered-piston which is under the control of cursize of said opening being inversely proportional to the tame-or said: current and mechanismtor delivering hydraulic fluid to sa'i'dhydraulic 1 feeding means asdeteririined by the pressure drop through said orifice.

5. In apparatus or the class describedthe combination-- with cutting mechanism; of a hydraulic motor for feeding said cutting mechanism, an electric motor for driving said cutting mechanism, mechanism for delivering hydraulic fluid to said hydraulic motor at a rate controlled by th current flowthrou'gh said electric motor to= maintain the load' dn itwithin safe limits including having" an orifice, means incluuirrga 7 avalve '7 tapered" pistonin said valve -orifice adjustable to a predetermined position accordance with said electricmotor versely proportional to saidcur-rent when the current iswithin the range of to o'fthe full rated current of said electric motor, and a volume control for the hydraulic fluid delivered to said hydraulic motor operated by the pressure drop across said orifice.

6. In apparatus of the class describedthe combination with cuttingmechanism, of a hydraulic motor for feedingsaid cutting: mechanism, an electric motor for driving 'sai'd cutting mechanism, mechanism for delivering hydraulid'fluid to'said hydraulic 'mot'or at aratecontrolled by the current-"fiowthrough said electric'mot'or to maintair'i the load "o'n 'it within safe limitsincludirig a'valve having an orifice, rn'eans-including a tapered piston within-said-orifice adjustable accordance with the current flow through saidelectric motor, and a volume control for the hydraulic fluid delivered to said hydraulic motor operated by the pressure across'saidorifice.

7:; apparatus of the class described the combination with a mainframe, of a -'c-utter mounted thereon, an ele'ctric motor for driving said cutter, hydraulic motor means for feeding said cutter; a hydraulic systemiincmding a pump for feeding hydraulic fluid to said hydraulic motor, valve means for lay-passing a variable amount of the hydraulic fluid output of; said pump and. delivering the rest. to said hydraulic system "for operating said hydraulic 'motor'm'eans, mechanismin: said hydraulic syste'miresponsive tothevolumeof hydraulic fluid flowing to said hydraulicmotor means and interconriected-to'said. valve means for controlling the rate oflby pass thereot, and mechanism responsiv'e Ltd the current flow through. said elec'tri'c motor? foradju'sting said first mentioned'mecha-- sai'd firstmentioned: mechanism including an orifice, a conical piston movable .thereinto to varyrits efiective size, means urging'said'piston to maximum orifice" opening position, and solenoid means opposing the action ofT'said urging means and actingdirectly on a plunger connected to. said piston'through'w-hich solenoid the current to said electric motor fiows. l. r

' it; 'Inapparatus of the classdescribed, the combination with a main frame, of a cutter mounted thereon, an electric motor for driving said cutter, hydraulic motor means -for feeding said cutter, a hydraulic system including a pump for-feeding hydraulic fiuid to said hydraulic motor, valve means for by-passing a variable amount of the hydraulic .fiuid'output of said pump and delivering the rest to 'said'hydraulic system .for operating said hydraulic motor means, mechanism in said hydraulic system responsive' to the volume of hydraulic fluidv flowing to said hydraulic motor means and interconnected to said valve means for controlling the rate of lay-pass thereof, "and mechanism'responsive'to the current flow through said electric motor for" adjustingsaid first men tionedmecha-nism, said first mentioned mechanism including'an orifice, a conical piston movab'lestherei-nto to' vary its efiective size, means urgingiisaid piston: to maximum orifice opening -position, hydrau1icl mechanism for adjusting said I pis'tonag'ainsti said urgingjmeans including a pilot valve, a solenoidfor adjusting'said pilot valve and connected in series with 'said electric motor, and a spririgopposing the actionof said solenoid.

9.,Ini apparatus ofv the class described, the combination with cutting. mechanism, ofa hydraulicmotor means for feeding, saidi cutting mechanism, an. electric motor for driving said cutting; mechanism, a pump, conduit means ,for

delivering hydraulic fluid from said pump to said hydraulic motor means while continuously bypassing a portion of the hydraulic'output of said pump, passageway means in saidconduit for restricting' the flow of fluid supplied to said hydraulic motor, mechanism for adjusting the effective'size of said restricted passageway to a predetermined value determined by the valuec-f the current flowing to said electric motor and variable inversely with variations in said current, and mechanism controlling said b-y-passing means as determined by the pressure drop'across said re-' and delivering the rest to said hydraulic system 7 for operating said hydraulic motor means, mechanism in said hydraulic system responsive to the volume of hydraulic fluid flowing to said hydraulic motor means and interconnected to said valve means for controlling the rate of by-pass thereof, and mechanism responsive to the current flow through said electric motor for adjusting said first mentioned mechanism, said first mentioned mechanism including an'orifice, a piston movable thereinto to vary its effectiv size, means urging said piston to maximum orifice opening position, and solenoid means opposing the action of said urging means and actingidirectly on a plunger connected to said piston through which solenoid the current to said electric motor flows.

11. In apparatus of the class described, the

combination with cutting mechanism,- of hydraulic motor means for feeding said cutting mechanism, an electric motor fordriving said cutting mechanism, a pump having an output in ex- ,cess of, the normal fluid consumption of said hydraulic motor means, conduit means for delivering hydraulic fluid from said pump tosaid hydraulic motormeans, a fluid by-pass control valve in said conduit means constructed normally to by-pass a portion of said hydraulic fluid during operation of said pump and hydraulic motor means, and mechanism operable by variations of therate of current flow to said motor .to control said by-pass valve to increase the fluid by-passed whenever said electric motor is over-loaded and to decrease the fluid by-passed whenever said electric motor is operating below its rated load whereby said electric motor is automatically maintained in operation substantially at it full rated load, said by-pass control valve having an orifice, and said last-mentioned mechanism including a tapered piston extending into said orifice.

'ROBERT K. JEFFREY.

STERLING C. MOON. 

